Adding unittest for blink gc dump provider.

Source/platform/heap/blink_heap.gypi

 #
 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 43 matching lines @@
       'StackFrameDepth.cpp',
       'StackFrameDepth.h',
       'ThreadState.cpp',
       'ThreadState.h',
       'ThreadingTraits.h',
       'TraceTraits.h',
       'Visitor.h',
     ],
     'platform_heap_test_files': [
       'HeapTest.cpp',
+      'BlinkGCMemoryDumpProviderTest.cpp',
     ],
     'conditions': [
       ['target_arch == "arm"', {
         'platform_heap_asm_files': [
           'asm/SaveRegisters_arm.S',
         ],
       }],
       ['target_arch == "arm64"', {
         'platform_heap_asm_files': [
           'asm/SaveRegisters_arm64.S',
@@ skipping 10 matching lines @@
         ],
       }],
       ['target_arch == "ia32" or target_arch == "x64"', {
         'platform_heap_asm_files': [
           'asm/SaveRegisters_x86.asm',
         ],
       }],
     ],
   },
 }